I have always used 6 inch rods
Better rod ratio
Less piston sticking out of the bottom of the bore at TDC with 6 inch rods
Pistons are liter
Balancing with a crank for a 6 inch rods will be internally where some 5.7 rod cranks have to be balanced exteranally.
From what I have seen 6 inch rods in a 383 seems more popular.